Gauge (or Gage) blocks are precision-ground, rectangular or square blocks made from high-quality steel, ceramic, or other materials. They are manufactured to very precise dimensions with extremely tight tolerances. Gage blocks come in various sizes, and they are used as building blocks to create precise measurement standards. By stacking gage blocks together in various combinations, technicians can create precise lengths that can be used as references for calibrating and checking other measuring instruments, such as micrometers, calipers, and height gauges.
Wringing is a crucial technique in the use of gage blocks that ensures their accurate measurement and calibration. It involves the careful attachment of two or more gage blocks together through the application of a slight force, utilizing the force of molecular attraction between their flat, polished surfaces. This creates a temporary bond that holds the gage blocks securely in place, forming a stable and accurate measurement reference. Wringing is essential because it minimizes the effects of minute gaps or imperfections between the blocks, which could introduce errors in measurements.